Physical Review Letters
Semiclassical Analysis of Quantum Spectral Functions for a Chaotic Billiard
B. Mehlig, D. Boosé, Kirsten Müller
Abstract
For a chaotic billiard, we calculate the quantum spectral functions associated with the position operator $\stackrel{^}{X}$ and the momentum operator ${\stackrel{^}{P}}_{x}$. Semiclassical analysis shows that the quantum spectral function is determined to a large extent by classical ergodic autocorrelations inherent in the Weyl part. For the first time, we calculate periodic orbit corrections to the spectral function.